Methods and apparatus for harvesting vaccine from eggs

ABSTRACT

Methods and apparatus for producing vaccine within a plurality of eggs are provided. Each of a plurality of eggs is illuminated with light from one or more LEDs. A detector is positioned adjacent each egg and detects light passing therethrough. Each egg is then identified as containing a live embryo or as being a non-live egg. Each egg that is determined not to contain a live embryo may be removed, either automatically or by hand. A seed virus is injected into each egg identified as containing a live embryo. After a predetermined period of incubation each live embryo is euthanized and amniotic fluid containing a vaccine produced as a result of the presence of a seed virus is harvested from each euthanized egg.

FIELD OF THE INVENTION

The present invention relates generally to eggs and, more particularly,to methods and apparatus for processing eggs.

BACKGROUND OF THE INVENTION

Discrimination between poultry eggs on the basis of some observablequality is a well-known and long-used practice in the poultry industry.“Candling” is a common name for one such technique, a term which has itsroots in the original practice of inspecting an egg using the light froma candle. As is known to those familiar with eggs, although egg shellsappear opaque under most lighting conditions, they are in realitysomewhat translucent, and when placed in front of a direct light, thecontents of the egg can be observed.

An egg may be a “live” egg, meaning that it has a viable embryo. FIG. 1Aillustrates a live poultry egg 1 at about day one of incubation. FIG. 1Billustrates the live egg 1 at about day eleven of incubation. The egg 1has a somewhat narrow end in the vicinity represented at 1 a as well asan oppositely disposed broadened end portion in the vicinity shown at 1b. In FIG. 1A, an embryo 2 is represented atop the yolk 3. The egg 1contains an air cell 4 adjacent the broadened end 1 b. As illustrated inFIG. 1B, the wings 5, legs 6, and beak 7 of a baby chick have developed.

An egg may be a “clear” or “infertile” egg, meaning that it does nothave an embryo. More particularly, a “clear” egg is an infertile eggthat has not rotted. An egg may be an “early dead” egg, meaning that ithas an embryo which died at about one to five days old. An egg may be a“mid-dead” egg, meaning that it has an embryo which died at about fiveto fifteen days old. An egg may be a “late-dead” egg, meaning that ithas an embryo which died at about fifteen to eighteen days old.

An egg may be a “rotted” egg, meaning that the egg includes a rottedinfertile yolk (for example, as a result of a crack in the egg's shell)or, alternatively, a rotted, dead embryo. While an “early dead”,“mid-dead” or “late-dead egg” may be a rotted egg, those terms as usedherein refer to such eggs which have not rotted. Clear, early-dead,mid-dead, late-dead, and rotted eggs may also be categorized as“non-live” eggs because they do not include a living embryo.

Eggs which are to be hatched to live poultry are typically candledduring embryonic development or later to identify clear, rotted, anddead eggs (collectively referred to herein as “non-live eggs”) andremove them from incubation to thereby increase available incubatorspace. U.S. Pat. Nos. 4,955,728 and 4,914,672, both to Hebrank, describea candling apparatus that uses infrared detectors and the infraredradiation emitted from an egg to distinguish live from infertile eggs.

U.S. Pat. No. 4,671,652 to van Asselt et al. describes a candlingapparatus in which a plurality of light sources and corresponding lightdetectors are mounted in an array, and wherein eggs are passed on a flatbetween the light sources and the light detectors.

Other applications where it is important to be able to distinguishbetween live and non-live eggs are becoming important. One of theseapplications is cultivation and harvesting of human flu vaccines vialive eggs. Human flu vaccine production is accomplished by injectingseed virus into a chicken egg at about day eleven of embryonicdevelopment (day-11 egg), allowing the virus to grow for about two days,euthanizing the embryo by cooling the egg, and then harvesting theamniotic fluid from the egg.

Typically, eggs are candled before injection of a seed virus to removenon-live eggs. The fluid surrounding virtually all early and mid-deadeggs in many hatcheries tend to have a white, milky appearance and arereferred to in the industry as “milky” eggs. It is surmised that theprocedure of washing an egg prior to incubation may produce a milky eggeither by the wash solution transporting pathogens into the egg orbecause the washing removes some of the protective cuticle on the eggshell. Unfortunately, the embryo of a Day-11 egg may block as much lightfrom a candling apparatus as a milky egg. As a result, it may bedifficult to distinguish between milky early dead eggs and live eggs atthis stage of embryonic development.

SUMMARY OF THE INVENTION

In view of the above discussion, embodiments of the present inventionprovide methods and apparatus for identifying whether an egg,particularly an egg at day eleven of incubation (day-11 egg), contains alive embryo. An egg is illuminated with light from a light emittingdiode (LED) at wavelengths of between about 650 nm-850 nm. Light passingthrough the egg is received at a detector positioned adjacent the egg,and the egg is then identified as containing a live embryo if detectedlight is less than a preset value, or the egg is identified as anon-live egg if detected light is greater than the preset value.

According to embodiments of the present invention, illuminating an eggmay include directing one or more pulses of light at an egg atwavelengths of between about 650 nm-850 nm. According to embodiments ofthe present invention, illuminating an egg may include directing a pulseof light having a peak wavelength of about 700 nm and a half-powerspectral width of less than about 100 nm at the egg.

According to embodiments of the present invention, identifying whetheran egg contains a live embryo may include illuminating the egg withlight from a first LED at wavelengths selected from the wavelength bandsconsisting of 830 nm-1000 nm, 710 nm-800 nm, 880 nm-900 nm, and withlight from a second LED at wavelengths selected from the wavelengthbands consisting of 700 nm-830 nm, 700 nm-775 nm, 830 nm-880 nm. Lightpassing through the egg is received by a detector positioned adjacentthe egg, and the egg is identified as containing a live embryo ifdetected light from the first LED is less than a first preset value andif the value of the detected light from the first LED divided by thevalue of the detected light from the second LED is less than a secondpreset value. Alternatively, the egg may be identified as a non-live eggif detected light from the first LED is greater than the first presetvalue and if detected light from the second LED divided by the detectedlight from the first LED is greater than the second preset value.

According to embodiments of the present invention, methods of producingvaccine within a plurality of eggs are provided. Each of a plurality ofeggs is illuminated with light from one or more LEDs. A detector ispositioned adjacent each egg and detects light passing therethrough.Each egg is then identified as containing a live embryo or as being anon-live egg. Each egg that is determined not to contain a live embryo(e.g., dead, clear, etc.) may be removed, either automatically or byhand. A seed virus (or multiple seed viruses) is injected in ovo intoeach egg identified as containing a live embryo.

After a predetermined period of incubation (e.g., between 2-5 days) eachlive embryo is euthanized and amniotic fluid (or other material)containing a vaccine produced as a result of the presence of a seedvirus is harvested from each euthanized egg.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a live chicken egg at about day one of incubation.

FIG. 1B illustrates a live chicken egg at about day eleven ofincubation.

FIG. 2 is a flowchart of operations for producing vaccines within aplurality of eggs, according to embodiments of the present invention.

FIG. 3 is a block diagram of a system for producing vaccines within aplurality of eggs, according to embodiments of the present invention.

FIG. 4 is a block diagram of a light source and detector for identifyingwhether an egg in day eleven of incubation (day-11 egg) contains a liveembryo, according to embodiments of the present invention.

FIG. 5 is a side view of a multiple injection head in ovoinjection/material removal device with which virus delivery devices andmethods, as well as material removal devices and methods, according toembodiments of the present invention may be used.

FIG. 6 is a graph showing the ability of a single beam to discriminatebetween live and non-live day 11 eggs.

FIG. 7 is a plot showing the combinations of wavelengths that allowdiscrimination between live and non-live day 11 eggs.

FIGS. 8-9 are graphs comparing the performance of various LED lightsources, according to embodiments of the present invention.

FIGS. 10-11 are plots that illustrate the discrimination ratio for twogroups of selected eggs using a number equal to the ratio of lightvalues at two different wavelengths.

DETAILED DESCRIPTION OF THE INVENTION

The present invention now is described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Methods and apparatus according to embodiments of the present inventionmay be utilized for identifying whether an egg contains a dead or liveembryo at any time during the embryonic development period (alsoreferred to as the incubation period) of the egg. Embodiments of thepresent invention are not limited to identification at a particular day(e.g., day eleven) during the embryonic development period. In addition,methods and apparatus according to embodiments of the present inventionmay be used with any types of avian eggs, including chicken, turkey,duck, geese, quail, and pheasant eggs.

Referring now to FIG. 2, a method of producing vaccine within aplurality of eggs, according to embodiments of the present invention, isillustrated. Each of a plurality of day-11 eggs is illuminated withlight from one or more light sources at wavelengths of between about sixhundred fifty nanometers and about eight hundred fifty nanometers (650nm-850 nm) (Block 100). Preferred light sources include light emittingdiodes (LEDs).

As is known to those skilled in the art, an LED is a semiconductordevice that emits light when an electric current is passed therethrough.The output from an LED can range from red (at a peak wavelength of about695 nanometers) to blue-violet (at a peak wavelength of about 400nanometers). LEDs that emit infrared (IR) energy (830 nanometers orlonger) may also be utilized in accordance with embodiments of thepresent invention.

Each light source is positioned adjacent an egg (e.g., at or near thepointed or non-air cell end of an egg). Each light source may be incontacting relationship with an egg, and/or a light beam from the lightsource may be collimated into a narrow beam (typically less than ±10degrees), such that less light will be scattered off adjacent eggs andinto the detector of an egg.

According to embodiments of the present invention, illuminating eachday-11 egg with light from one or more light sources may includedirecting one or more pulses of light at each egg at wavelengths ofbetween about six hundred fifty nanometers and about eight hundred fiftynanometers (650 nm-850 nm). According to other embodiments of thepresent invention, illuminating an egg with light from one or more lightsources may include directing a pulse of light having a peak wavelengthof about 695 nanometers and a half-power spectral width of less thanabout 100 nanometers at each egg.

According to embodiments of the present invention, dual light sourcesmay be utilized to direct one or more pulses of light at each egg in thefollowing wavelength bands:

Wavelength A Wavelength B 830-1000 nm 700-830 nm 710-800 nm 700-775 nm880-900 nm 830-880 nm

A detector is positioned adjacent each egg and detects light passingtherethrough (Block 110). Each egg is then identified as containing alive embryo or as being a non-live egg (Block 120). According toembodiments of the present invention, an egg contains a live embryo ifdetected light is less than a preset value and an egg is a non-live eggif detected light is greater than the preset value. A preset value maybe a particular intensity of light. For example, a preset value may be acertain level (e.g., 0.1 microwatt per square centimeter) and/or may bea certain percentage of transmitted light within one or more frequencybands, or the ratio of the transmitted light at two differentwavelengths.

According to embodiments of the present invention, a light source anddetector may be positioned on respective opposite portions of arespective egg. For example, each respective light source and detectormay be positioned on respective opposite end portions of an egg.However, a light source and a detector need not be positioned directlyopposite from one another. A light source and detector may be positionedadjacent an egg in any of various configurations and orientations,without limitation.

Each egg that is determined not to contain a live embryo (e.g., dead,clear, cracked, rotted, etc.) may be removed, either automatically or byhand (Block 130). Removed eggs may be discarded or may be subjected toadditional processing for various purposes. A seed virus (or multipleseed viruses) is injected into each egg identified as containing a liveembryo (Block 140). For example, a human flu virus may be injected intoeach egg identified as containing a live embryo.

An exemplary device for injecting a seed virus into a plurality of eggsin accordance with embodiments of the present invention is theINOVOJECT® automated injection system (Embrex, Inc., Research TrianglePark, N.C.). However, any in ovo injection device may be suitable foruse according to embodiments of the present invention. Suitableinjection devices preferably are designed to operate in conjunction withcommercial egg carrier devices or flats.

After a predetermined period of incubation (e.g., between 2-5 days) eachlive embryo is euthanized (Block 150) and amniotic fluid (or othermaterial) containing a vaccine produced as a result of the presence of aseed virus is harvested from each euthanized egg (Block 160). Forexample, if a seed virus injected into an egg is a human flu virus, theharvested amniotic fluid (or other material) contains human flu vaccine.

Referring now to FIG. 3, an apparatus 20 for producing vaccine within aplurality of eggs according to embodiments of the present invention isillustrated. The illustrated apparatus 20 includes a classifier 22 thatis configured to identify eggs containing live embryos and to identifynon-live eggs from among a plurality of eggs 1 in an incoming egg flat8. The classifier 22 is operatively connected to a controller 30 whichcontrols the classifier 22 and stores information about each egg 1(e.g., whether an egg contains a live embryo or not, etc.). Theclassifier 22 includes a plurality of light sources (LEDs) and detectorsoperably associated with a respective egg 1 in the flat 8. An operatorinterface (e.g., a display) 32 is preferably provided to allow anoperator to interact with the controller 30.

FIG. 4 illustrates an exemplary light source (e.g., an LED) 24 and lightdetector 26 positioned adjacent opposite portions of an egg 1. Accordingto a preferred embodiment, an illumination beam is generated by a 700 nMLED (ELD-700-524-3 from Roithner Lasertechnik, Vienna Austria) having a±10 degree beam angle located approximately 2 cm above an egg. The LEDis placed in a cavity approximately 2 cm deep and 2 cm in diameter witha 0.8 cm diameter aperture. The cavity and aperture function asdescribed in U.S. Pat. Nos. 5,900,929 and 5,745,228, which are assignedto the assignee of the present invention, and which are incorporatedherein by reference in their entireties, to reduce stray light that isemitted outside of the central beam.

A preferred detector is an IPL 10530DAL, from Integrated PhotomatrixLimited, Dorchester Dorset, UK and is mounted about 2 cm from an egg anddirectly below it. According to an embodiment of the present invention,there is one emitter-detector pair for each position in a row of eggs sothat as a flat of eggs passes under the unit all eggs on the flat willbe scanned by the array. Emitters are pulsed on for about 70microseconds, one at a time, to eliminate light from one egg reflectinginto an adjacent detector. The output of each detector is recordedimmediately before its LED is pulsed on, during the on time, andafterwards. The recorded reading is the detector output while the LED ison minus the average of the light levels before and after that period.The scanning pattern allows each egg in a row to be sampled about 200times per second.

Embodiments of the present invention do not require that a respectivelight source (or sources) and detector be provided for each egg in aflat. Various numbers and combinations of light sources and detectorsmay be utilized without limitation.

An egg removal station 40, seed virus injection station 50, and vaccineharvesting station 70 are provided downstream of the classifier 22 andare each operatively connected to the controller 30. The seed virusinjection station 50 is configured to inject one or more seed virusesinto each egg 1 within a flat 8 that is identified as containing a liveembryo.

FIG. 5 illustrates an exemplary apparatus 80 that may be utilized toinject a seed virus into a plurality of eggs in ovo, as well as toremove material from a plurality of eggs, according to embodiments ofthe present invention. The illustrated apparatus 80 includes a flat 8for carrying eggs 1, a stationary base 82, and a plurality of injectiondelivery devices, or heads, 85 with fluid delivery means such as lumensor needle(s) positioned therein in accordance with known techniques. Theflat 8 holds a plurality of eggs 1 in a substantially upright position.The flat 8 is configured to provide external access to predeterminedareas of the eggs 1. Each egg 1 is held by the flat 8 so that arespective end thereof is in proper alignment relative to acorresponding one of the injection heads 85 as the injection head 85advances towards the base 82 of the apparatus. However, in ovo injection(and in ovo material removal) devices may inject (or remove materialfrom) eggs in various orientations. Embodiments of the present inventionare not limited only to in ovo injection and/or removal devices thatinject (or remove material from) eggs in the illustrated orientation.

Each of the plurality of injection heads 85 has opposing first andsecond ends 86, 87. The heads 85 have a first extended position and asecond retracted position, as is known in the art. Upon extension of aninjection head 85, the first end 86 is configured to contact and restagainst predetermined areas of an external egg shell. When not injecting(or removing material from an egg), the injection heads 85 are retractedto rest a predetermined distance above the eggs 1 and stationary base82. Alternatively, the base 82 can be longitudinally slidably moveableto position the eggs 1 in proper position relative to the injectionheads 85.

Referring back to FIG. 3, the egg removal station 40 is configured toremove eggs identified as non-live. The controller 30 generates aselective removal signal for an egg 1 based upon whether the classifier22 identified the egg 1 as being non-live. The egg removal station 40may employ suction-type lifting devices as disclosed in U.S. Pat. No.4,681,063 or in U.S. Pat. No. 5,017,003 to Keromnes et al., thedisclosures of which are hereby incorporated by reference in theirentireties. Various devices and methods for removing eggs may beutilized with embodiments of the present invention without limitation.Exemplary egg removal apparatus that may serve the function of the eggremoval station 40 are described in U.S. Pat. Nos. 6,145,668; 6,149,375;6,213,709; and 6,224,316, each of which is incorporated herein byreference in its entirety.

The egg removal station 40 preferably operates automatically androbotically. Alternatively, selected eggs may be identified on the userinterface 32, optionally marked, and removed by hand.

After injection with a seed virus, the eggs 1 containing live embryosare transferred to an incubator 60 for a predetermined period of time.At the end of this period of time, the eggs 1 are transferred to thevaccine harvesting station 70 where material from each egg 1 (e.g.,amniotic fluid) is extracted. An exemplary device that may be adaptedfor use as a vaccine harvesting device in accordance with embodiments ofthe present invention is the INOVOJECT® automated injection system.

The controller 30 preferably includes a processor or other suitableprogrammable or non-programmable circuitry including suitable software.The controller 30 may also include such other devices as appropriate tocontrol the classifier 22, the egg removal station 40, the seed virusinjection station 50, the incubator 60, and the vaccine harvestingstation 70. Suitable devices, circuitry and software for implementing acontroller 30 will be readily apparent to those skilled in the art uponreading the description herein and the disclosures of U.S. Pat. No.5,745,228 to Hebrank et al. and U.S. Pat. No. 4,955,728 to Hebrank,which are incorporated herein by reference in their entireties.

The operator interface 32 may be any suitable user interface device andmay include a touch screen and/or keyboard. The operator interface 32may allow a user to retrieve various information from the controller 30,to set various parameters and/or to program/reprogram the controller 30.The operator interface 32 may include other peripheral devices, forexample, a printer and a connection to a computer network.

According to alternative embodiments of the present invention, one ormore of the stations (40,50,60,70) described with respect to FIG. 3 maybe controlled by individual programmable logic controllers (PLCs). Datamay be transferred back and forth from a PLC to a central computerdatabase controller for storage. For example, a central database may beprovided to store information about eggs being processed. The centralcomputer database controller may be configured to respond to individualPLCs when they request data or send data. The central computer databaseneed not directly control the various stations under the control ofrespective PLCs.

A conveying system 18 serves to transport a flat 8 of eggs 1 throughand, optionally, between, the classifier 22, the egg removal station 40,the seed virus injection station 50, the incubator 60, and the vaccineharvesting station 70. Egg conveying systems are well known to those ofskill in the art and need not be described further herein.

Although eggs conventionally are carried in egg flats, any means ofpresenting a plurality of eggs over time to the classifier 22, the eggremoval station 40, the seed virus injection station 50, the incubator60, and the vaccine harvesting station 70 can be used.

Egg flats of virtually any type may be used in accordance withembodiments of the present invention. Flats may contain any number ofrows, such as seven rows of eggs, with rows of six and seven being mostcommon. Moreover, eggs in adjacent rows may be parallel to one another,as in a “rectangular” flat, or may be in a staggered relationship, as inan “offset” flat. Examples of suitable commercial flats include, but arenot limited to, the “CHICKMASTER 54” flat, the “JAMESWAY 42” flat andthe “JAMESWAY 84” flat (in each case, the number indicates the number ofeggs carried by the flat). Egg flats are well known to those of skill inthe art and need not be described further herein.

Embodiments of the present invention are not limited just to eggslocated in flats prior to vaccine production, but may also be applied todiscriminating eggs just prior to or in the process of harvestingvaccine in a vaccine production process. Embodiments of this inventionmay also be used for collecting data that is used to predict the numbersof eggs that will hatch in situations where milky eggs are present evenin smaller quantities such as Day 9 to 14 eggs in a broiler hatchery.

Experimental Data

In order to discover the combinations of LED light sources that wouldbest discriminate among live Day-11 and milky eggs, extensivespectrophotometer data for these types of eggs was collected andanalyzed to establish optimal regions. FIG. 6 is a plot of the potentialfor discriminating between live and milky eggs using LED generated lightof different wavelengths. Note that wavelengths between 600 and 850 nMare much more effective than visible or 880 nM light, and the range from650 to 820 is most effective. This plot was created in the followingmanner:

1. Two groups of approximately 1300 Day-11 eggs were run tested by astandard Embrex 880 nM Identifier. The 5% of the eggs that had lightvalues closest to the live-dead cutoff value were selected, hand candledand broken out to establish embryo condition. In the difficult to screengroup were 51 live and 30 milky eggs from a January flock and 43 liveand 24 milkies from a March flock.

2. Spectrometry data was collected for these two groups of eggs byshining a narrow beam of light from a tungsten halogen light downwardsat the top (aircell end) of each egg. A fiber optic cable andcollimating lens aimed at the bottom of each egg carried light to anOcean Optics spectrometer. The spectrometer gave the light intensity fortwo thousand light wavelengths evenly spaced between 400 nM and 1000 nM.Each value was effectively the transmissibility of each egg at thatwavelength.

3. The two thousand points of spectral data for each egg were used tosynthesis an effective transmissivity of light that would occur at awide bandwidth detector when from light from an LED having a half-powerspectral band of ±35 nanometers was shined at the top of each egg. Thiswas done for each of about 110 imaginary LEDs with center wavelengths at5 nM intervals from 420 to 980 nM.

4. Using the light values projected to be transmitted through eggs foreach imaginary LED, the mean and standard deviation statistics werecalculated for the live and milky eggs from each flock. A quantitativemeasure of the accuracy of discrimination between lives and milkies wasdefined as the arithmetic difference between the live and milky meansdivided by the square root of the sum of the square of the live standarddeviation and the square of the milky standard deviation. A largediscrimination value thereby indicates that the two groups of eggs havevery different light values at that wavelength relative to the variationwithin each group.

5. This data is plotted in FIG. 6 for the two groups of live and milkyeggs. Note that these eggs were preselected to be the live and milkyeggs out of 1300 eggs that are most difficult to discriminate with 880nM LED technology, so that the discrimination ratios predict whichwavelengths work best for the eggs that are most difficult todiscriminate. The discrimination values are not true discriminationvalues for the entire population of eggs.

The same data set was used to discover the combinations of LED lightsources that would discriminate lives from milkies based upon a ratio ofreceived light intensities. This data is plotted in FIG. 7. In this caseanalysis was done to discover that the ratios of intensities at the twowavelengths gave the highest discrimination values. In FIG. 7, there arezones of discrimination values. Here, orange is a high value, and lightblue is lowest. Discrimination values better than 1.5 give good machineperformance.

FIG. 8 is a graph that compares the performance of a standard 880 nMIdentifier, a 700 nM single-beam Identifier, a dual Beam Identifierusing 760 and 880 nM (Ideal) and 750 and 880 nM “test” dual beam unit.The eggs used were the select group of the 5% most difficult to classifyeggs as determined by the standard 880 nM Identifier. The percentage ofthe eggs classified correctly using as a cutoff the one live egg whosevalue is nearest the milky eggs. Note that one live egg believed to be arunt with a light level more than three times the mean live egg value onthe 880 Identifier was excluded from this comparison.

FIG. 9 is a graph that compares the performance of the standard 880 nMIdentifier, a 700 nM single-beam Identifier and a dual Beam Identifierusing 760 and 880 nM (Ideal). The eggs used were the select group of the5% most difficult to classify eggs as determined by the standard 880 nMIdentifier. Detection ratio was calculated as the difference between themeans of the lives and dead eggs divided by the square root of the sumof the squares of the standard deviations of the two groups.

FIGS. 10-11 are respective plots showing the discrimination ratio forthe two groups of selected eggs using a number equal to the ratio oflight values at two different wavelengths. High values indicate the meanvalues for the lives and milkies are well separated relative to theirvariation. The two groups of eggs are the 5% most difficult to separateeggs in the January (Group 1) and March (Group 2) flocks.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although a few exemplary embodiments ofthis invention have been described, those skilled in the art willreadily appreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. The invention is defined by the following claims, withequivalents of the claims to be included therein.

1. A method of identifying whether an egg contains a live embryo,comprising: illuminating the egg with one or more pulses of light from alight source at wavelengths of between about 650 nm-850 nm for a timeperiod of less than or equal to about 1 second, wherein the one or morepulses of light have a peak wavelength of between 650 nm and 820 nm anda half-power spectral width of less than about 100 nm; receiving lightpassing through the egg at a detector positioned adjacent the egg; andidentifying the egg as containing a live embryo if detected light isless than a preset value, or identifying the egg as a non-live egg ifdetected light is greater than the preset value.
 2. The method of claim1, wherein the light source and detector are positioned on respectiveopposite portions of the egg.
 3. The method of claim 2, wherein thelight source and detector are positioned on respective opposite endportions of the egg.
 4. The method of claim 1, wherein the light sourcecomprises a light emitting diode (LED).
 5. The method of claim 1,wherein the egg is in day eleven of incubation (day-11 egg).
 6. A methodof producing a vaccine within a plurality of eggs, comprising:illuminating each egg with one or more pulses of light from a lightsource having a peak wavelength of between 650 nm and 820 nm and ahalf-power spectral width of less than about 100 nm for a time period ofless than or equal to about 1 second; receiving light passing througheach egg by a detector positioned adjacent each egg; identifying a eggas containing a live embryo if detected light for the egg is less than apreset value, or identifying the egg as a non-live egg if detected lightfor the egg is greater than the preset value; and injecting a virus intoeach egg identified as containing a live embryo.
 7. The method of claim6, further comprising discarding each egg identified as a non-live egg.8. The method of claim 6, wherein the light source and detector arepositioned on respective opposite portions of each egg.
 9. The method ofclaim 8, wherein the light source and detector are positioned onrespective opposite end portions of each egg.
 10. The method of claim 6,wherein the light source comprises a light emitting diode (LED).
 11. Themethod of claim 6, further comprising: euthanizing an embryo in each eggidentified as containing a live embryo; and harvesting amniotic fluidfrom each euthanized egg, wherein the amniotic fluid comprises vaccine.12. The method of claim 11, wherein the virus comprises human flu virusand wherein the harvested amniotic fluid comprises human flu vaccine.13. The method of claim 6, wherein the egg is in day eleven ofincubation (day-11 egg).